This application claims priority to Japanese patent application number 2001-211005 filed Jul. 11, 2001, the contents of which are hereby incorporated herein by reference.
1. Technical Field
The present invention relates to truing devices for correcting warpage of necks of stringed instruments and, more particularly, to guitars equipped with such truing devices.
2. Description of the Related Art
When stings are tightened on the neck of a guitar, the guitar neck may warp or bend toward the front side of the guitar due to the tension of strings. In order to correct or eliminate such warpage of the neck, neck truing devices have been proposed. FIGS. 8(A) to 8(D) show a known neck truing device 50 that may be disposed within a longitudinal recess S formed in a neck body M of a neck N of a guitar so as to extend along the longitudinal direction of the neck N, as shown in FIG. 8(E).
Referring to FIGS. 8(A) to 8(D), the known neck truing device 50 includes a first bar-shaped member 52 having a substantially U-shaped cross section. A second bar-shaped member 54 is disposed within the first bar-shaped member 52 and serves as a core. A stopper 54s is formed at the forward end (left end as viewed in FIG. 8(A)) of the second bar-shaped member 54 and is disposed externally of the forward end of the first bar-shaped member 52. A nut 56 is fitted into the rear end portion of the first bar-shaped member 52, so that the nut 56 can rotate relative to the first-bar-shaped member about the longitudinal axis. A female thread 56w is defined within the nut 56. A male thread 54m is defined on the base end portion of the second bar-shaped member 54 and threadably engages the female thread 56w. A plate 58 is disposed between a bottom surface 52b (upper surface as viewed in FIG. 8(A)) of the U-shaped groove defined within the first bar-shaped member 52 and an upper surface of the second bar-shaped member 54. As shown in FIG. 8(C), the second bar-shaped member 54 is partially curved or bent before the device 50 is disposed within the neck N.
According to this known arrangement, when an operator tightens the nut 56, a tensile force is produced and is applied to the second bar-shaped member 54 due to the threaded engagement of the male thread 54m and female thread 56w. As a result, the second bar-shaped member 54 causes the first bar-shaped member 52 to curve upwards from the position shown in FIG. 8(C) by cooperating with the plate 58 (See FIG. 8(D)). As shown in FIG. 8(E), the device 50 is embedded along the longitudinal recess S of the neck N such that the bottom surface 52b of the U-shaped groove of the first bar-shaped member 52 is positioned on the front side (upper side of as viewed in FIG. 8(E)) of the neck N. A finger board F is attached to the neck N, so that the device 50 is fixedly enclosed within the neck N. Therefore, by adjusting the degree of curvature of the first bar-shaped member 52 by means of the nut 56, it is possible to correct warpage of (i.e., true or straighten) the neck N, which warpage may be caused due to the tension applied across the neck N by the strings.
The curvature of the first bar-shaped member 52 of the known neck truing device 50 can be varied in one direction by tightening the nut 56 in order to cope with the warpage of the neck N caused by the tension of the strings. However, the device 50 cannot cope with warpage in other directions. For example, depending on the condition of the material of the neck N (typically, the neck N is made of wood), the neck N may possibly warp toward the rear side of the guitar against the tension of the strings applied to the neck N. In such cases, the known truing device 50 cannot correct warpage of the neck N.
Therefore, it is one object of the present teachings to provide improved devices for correcting warpage of necks of stringed instruments. For example, in one aspect of the present teachings, neck truing devices may include a first member that is adapted to be fixedly disposed within the neck of the string instrument. A second member may be coupled to the first member and may be connected between or across the respective ends of the first member. An adjusting mechanism may serve to apply a first force and a second force to the first member via the second member in order to respectively correct the warpage of the necks in opposing directions. According to the present specification, the term xe2x80x9ctruingxe2x80x9d is intended to mean adjusting or restoring the neck to a desired mechanical accuracy or form. If the neck of the stringed instrument is normally straight, then the neck truing device may be utilized to straighten the neck, if the neck has warped. However, the necks of some stringed instruments are normally curved. Thus, in such cases, the neck truing device may be utilized to return the neck to the desired curved configuration.
In one embodiment of the present teachings, the first member may be bent in a first direction when the first bending force is applied to the first member. On the other hand, the first member also may be bent in a second direction opposite to the first direction. In this case, when the neck has been warped toward a front side of the neck due to string tension, the first force may be applied to bend the neck toward the rear side by the adjusting mechanism so as to eliminate the warpage. On the other hand, when the neck has been warped toward the rear side, the second force may be applied to bend the neck toward the front side by the adjusting mechanism so as to eliminate the warpage in the rear side. As a result, warpage of the neck can be appropriately corrected or eliminated in response to the direction of warpage.
In another aspect of the present teachings, the adjusting mechanism may include a pull/push mechanism that may apply a pulling force and a pressing force to one end of the first member via the second member. In another aspect of the present teachings, one end of the first member may be fixedly connected to one end of the second member and the pull/push mechanism may be interposed between the other end of the first member and the other end of the second member. In another aspect of the present teachings, the pull/push mechanism may include a screw that is operable by an operator.
In another aspect of the present teachings, a control device may serve to control the bending direction of the first member in response to application of the respective first and second forces.
In another aspect of the present teachings, guitars are taught that may include the truing devices according to the aforementioned various aspects.
Additional objects, features and advantages of the present invention will be readily understood after reading the following detailed description together with the accompanying drawings and the claims.